The silver value of United States coins is contingent upon their year of mintage and denomination, as the composition of circulating currency changed significantly in the mid-20th century. For much of US history, coins contained a high percentage of silver, giving them intrinsic bullion value in addition to their face value.
The most commonly encountered silver coins are those composed of 90% silver and 10% copper. This composition applies to all dimes, quarters, and half dollars minted for circulation in the year 1964 or any prior year. Likewise, silver dollars, such as the Morgan and Peace dollar series, that were minted in 1935 or earlier also consist of this 90% silver alloy. The value of these coins is therefore directly tied to the spot price of silver.
A notable exception to this standard occurred after the Coinage Act of 1965. While silver was removed from dimes and quarters, the Kennedy half dollar continued to be minted with a reduced silver content. From 1965 through 1970, these half dollars were produced with a 40% silver clad composition.
Another distinct category of silver coinage emerged during World War II. To conserve the strategic metal nickel for the war effort, the composition of the five-cent piece was altered. Jefferson nickels minted from the middle of 1942 through 1945 contain 35% silver. These "War Nickels" are easily identifiable by the large mint mark (P, D, or S) located on the reverse side, above the dome of Monticello. After 1970, silver was removed from all circulating US coins.
